1. Field of the Invention
This invention relates to insulated pipes. In particular, this invention relates to insulated pipe anchors or restraints for insulated pipes.
2. Description of the Prior Art
Typically, prior art cryogenic pipe anchors are pre-assembled in a factory and delivered to the field with insulated pipe sections already contained within the anchor. The anchor housings are configured as a unitary cylindrical housing that encircles a pipe section and slipped over the end of a pipe section. With the housing and pipe section coaxially aligned, insulation material is injected into the annulus defined between the housing and the pipe section.
Other prior art anchors may be clamped onto the pipeline in the field. These clamp-on anchors have multi-section housings that are less stable than the unitary housings provided with pre-assembled housings. Prior art clamp-on anchor products did not address the issues of pipe rotation and aligning the top and bottom cradles. By not restricting the pipe rotation within the anchor, that pipe would rotate and translate the forces, which should have been contained by the anchor, to another location along the pipe. The housing sections too easily become misaligned with one another so that the majority of the axial forces in the pipeline acts upon only some portion of the housing.
There is a need for a clamp-on anchor that can be assembled to a pipeline in the field that positively aligns multiple housing sections and uniformly supports the pipeline against axial and rotational movements.